I decided to do an investigation into this phenomenon in order to determine if I and others were just crazy. I have tried to be as scientific as possible here. I'll give a short description of the tests I performed, and then present the full methods and data afterwards. I hope, that by setting out exactly what I did and how I did it, the transparency will allow anyone else to perform the same test and confirm my results, or suggest improvements to the methodology (just like actual SCIENCE!).
My setup was to create a custom map which was exactly symmetrical, consisting of two identical outposts at opposite ends of the map containing mining drills (to attract biters) and laser turrets (to kill the biters). Each outpost had an identical biter base next to it, from which it would suffer regular attacks. The intensity of attacks is measured by observing the amount of power drained from that outpost's accumulator banks, each biter killed taking approximately the same number of shots and thus the same energy drain.
The test was to position the player either in the left outpost, the right outpost or leave them in the centre, and measure the remaining energy in each outposts accumulators after 30 minutes in game. I did 16 trials, 4 in the centre, 6 at the left outpost and 6 at the right outpost. The trials at each outpost each had 2 replicates standing just inside the closed gates, on the gates and just outside the closed gates. In all situations the player was at least 3 chunks from the biters, with the bases only just coming on screen at maximum zoom out.
Left outpost setup:
The short answer is that it makes a massive difference. The player being located near a base increased the number of attacking biters by a factor of 3 (approximately). The player being in the centre caused neither base to suffer particularly strong attacks.
The statistical analysis shows that this result cannot be a fluke.
This table shows the position of the player (L = left outpost / R = right outpost / C = centre) and the energy remaining (in MJ, out of a max possible 500MJ) in each outpost's capacitor network after 30 minutes.
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Position EnergyL EnergyR L 321 443 R 392 141 C 439 440 C 439 439 L 294 409 R 444 136 L 398 451 R 371 93 C 439 440 C 439 440 L 420 403 R 449 229 L 357 462 R 426 77 L 363 421 R 443 72
The symbol (L/R/C represents what the player position was, and the x and y values are the remaining energy in each base for that single trial. From this picture it is clear what the statistical analysis will show: if the player position had no effect, then all the results should be clustered together, and have the same values as the C's (but they certainly don't). Note: The variance on the Centre trial is very low, so all the C's are basically on top of one another.
I performed a pair of one way ANOVA tests on the data.
Energy remaining in Left outpost accumulators:
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Df Sum Sq Mean Sq F value Pr(>F) Position 2 18784 9392 7.587 0.00656 ** Residuals 13 16094 1238
Energy remaining in Right outpost accumulators:
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Df Sum Sq Mean Sq F value Pr(>F) Position 2 360848 180424 116.1 5.11e-09 *** Residuals 13 20202 1554
I then performed a Tukey's Honest significant differences test to establish what effect player position has:
For Left energy:
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diff lwr upr p adj L-C -80.16667 -140.135560 -20.19777 0.0096332 R-C -18.16667 -78.135560 41.80223 0.7096269 R-L 62.00000 8.362191 115.63781 0.0234878
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diff lwr upr p adj L-C -8.2500 -75.43793 58.93793 0.943949 R-C -315.0833 -382.27126 -247.89541 0.000000 R-L -306.8333 -366.92804 -246.73863 0.000000
A multivariate-ANOVA might be appropriate, but I don't think it is necessary.
It is impossibly unlikely that biter attacks are independent of player position.
Have I just wasted my time here? Would anyone like to repeat my experiment? Did anyone even read through this?
I'm happy to answer any questions anyone has about the methods or results, so please ask if there is something unclear.
The energy in the accumulators is provided by independent bank of steam engines for each outpost, which have boilers containing 1GJ of fuel, thus providing 500MJ, exactly enough to fill the 100 accumulators in the outpost. There is also a single steam engine with unlimited fuel (at least 90 minutes worth) which provides a base output (510kW) exactly equivalent to the drain of the 85 laser turrets in the outpost. Without attack, the energy stored for each base remains constant after the few minutes it takes the main generators to exhaust their fuel supply.
The two electricity networks are certainly separate, but I brought power lines from both networks to the gates of both bases so I could check the energy levels in both simultaneously.
I did note that when I originally had actual walls (as opposed to the destroyed walls it now starts with) as distance markers the biters would attack a couple of the walls when the map started, but then not do anything to them thereafter. If I walked to an outpost, however, then as soon as I could see the walls nearest their bases the biters would start attacking them. This is perhaps an easier test than what I actually did, but harder to statistically analyse...
I used laser turrets and energy as opposed to gun turrets so that I could look into each network at the same time. I suppose I could have used logistic network and gun turrets and been able to do the same thing if the main ammo stores were in logistic chests.
The map is not actually perfectly symmetric, as I didn't check chunk boundaries when making it. The miners in the right base are half a chunk closer to the biter bases, which would explain why that base suffers stronger attacks.
The Centre player position runs are very consistent in terms of energy use. This may be because they suffer the fewest attacks, or it might be due to the deterministic nature of the game meaning the very minimal player input leads to very small divergence over the 30 minutes between trials. I'm not sure exactly what is going on as I didn't look at energy use over time, just the total used, and obviously from the centre I can't see the bases properly. I did record use every 60 seconds for two runs, but after that soul destroying exercise I just watched TV and recorded after 30 mins. It might be possible to use the warning icons to judge this, but again it requires actually sitting through it all.
The mini-map and the full map don't work properly, and you can't see terrain outside of the starting chunk or biters. This is probably because in the editor I made the map 1 by 1 tiles originally, then expanded it out in the editor with a big brush, so presumably as far as the map is concerned all that space doesn't exist.